Of these top 10 convenience store chains, eight also appeared on this year's Convenience Store News Top 20 Growth Chains ranking. Specifically, QuikTrip was No. 6; Wawa tied with RaceTrac for No. 17; Casey's General Stores was No. 7; Alimentation Couche-Tard Inc. (parent of Circle K) was No. 4; 7-Eleven was No. 1; Valero Corner Stores was No. 8; and Shell was tied for No. 15.

The Market Force study looked into which c-store chains consumers frequent the most, as well as why they prefer one to another. Market Force first calculated the favorites based on total votes, and then factored in the number of convenience stores for each chain to come up with a weighted view of the results. Of the 45 chains studied, 7-Eleven and Shell initially amassed the highest number of votes, which can be attributed to the fact that they have more than 10,000 locations in North America. However, when viewed as a calculation of votes per location, QuikTrip ranked first, according to the consumer research firm.

Market Force found consumers place a high value on the customer experience -- from appearance to amenities -- when visiting a convenience store. Store cleanliness, in particular, plays an important role in a consumer's decision about where to shop. When asked what they like most about their favorite chain, cleanliness was named more than any other factor. Friendly service ranked second, followed by amenities, coffee and great service.

"The top five factors relate to fundamental customer experience, and that's no surprise to the best players in the industry," said Janet Eden-Harris, chief marketing officer for Market Force. "Convenience store customers are on the go and in a hurry, but they will proactively drive to a store that provides a pleasant environment -- clean, friendly, great food and service. The payoff for convenience store operators is that consumers shop longer and spend more. If stores can excel in these areas, they'll see customers make a point to return again and again."

Leaders of the PackWhen it came to attributes such as cleanliness, amenities and atmosphere, QuikTrip and Wawa dominated across the board, ranking first and second in every category, according to the study.

Overall-favorite QuikTrip emerged as the clear leader in the friendliness and great service categories. It also ranked first for cleanliness, amenities and atmosphere. Wawa, Pa.-based Wawa was recognized for the quality of its coffee, while Atlanta-based RaceTrac performed consistently well in all of the attributes, securing a third-place spot in four of the six categories. Speedway, ExxonMobil and Casey's General Stores also outperformed many of the other chains studied in these key areas, according to Market Force.

"QuikTrip has done an exceptional job differentiating itself in customer service. Its focus on delivering a welcoming and efficient customer experience led it to stand out in satisfaction-driven categories, including friendly associates and great service," said Eden-Harris. "Given its success in these areas, it was little surprise to see QuikTrip claim the title of most popular convenience store chain."

Food for ThoughtPrepared and fast-food sales are steadily increasing in convenience stores across the United States and Canada -- a fact not lost on convenience retailers as they begin to expand their food offerings and seating options. Product selection and pricing are also growing in importance and present a sizeable opportunity for store operators to stand apart from the pack, the research firm stated.

The study found QuikTrip and Wawa ranked first and second in nearly every food and product attributes category. Wawa only dropped in promotions. Enon, Ohio-based Speedway took the top spot in promotions at 36 percent, followed by QuikTrip at 35 percent, RaceTrac at 26 percent and Wawa at 22 percent.

In addition, QuikTrip was the clear leader in merchandise selection (48 percent) and in merchandise prices (35 percent). It slightly edged out Wawa in food quality and fell second to Wawa in food selection.

Ankeny, Iowa-based Casey's General Stores and RaceTrac likewise performed consistently well in most food and product attributes categories, with RaceTrac placing in the top five across the board. Irving, Texas-based ExxonMobil made a showing in the merchandise prices category, and BP for promotions.

Brand LoyaltyThe Market Force study also found that more than a quarter of consumers are willing to drive past competitors to shop at their favorite convenience store brand, and 17 percent said they always choose their favorite brand over other competitive brands, even if the competitor's price is a little lower.

This is all especially true for QuikTrip, Wawa, Speedway, RaceTrac and ARCO/ampm. Forty-eight percent of survey respondents said they'd drive past a competitor to shop at QuikTrip; 46 percent said they'd do so for Wawa; 35 percent for Speedway; 34 percent for RaceTrac; and 28 percent for ARCO/ampm.

Market Force conducted the survey across the United States and Canada in April. The pool of 7,633 respondents reflected a broad spectrum of income levels, with 60 percent reporting household incomes of more than $50,000 a year. Respondents' ages ranged from 18 to over 65. Approximately 52 percent of participants were men and 48 percent were women, with nearly half having children at home.